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141.
Marchevsky AM Lau SK Khanafshar E Lockhart C Phan A Michaels PJ Fishbein MC 《Human pathology》2002,33(4):410-414
Current Internet-based teleconferencing techniques allow a referring pathologist to transmit real-time images from a microscope to a consultant, while maintaining a verbal conversation using Internet telephony. In our study, 50 randomly selected transbronchial biopsies from lung allograft recipients and 58 randomly selected endomyocardial biopsies from heart transplant patients were diagnosed by consultant pathologists using Internet-based teleconferencing methods. The referring pathologists acquired the real-time video images from the biopsies using a light microscope equipped with a phototube adapter and a video camera. The consultant pathologists viewed the processed images on a video monitor at 800 x 600 resolution, using a standard microcomputer equipped with Netmeeting software, and directed the referring pathologist to move the slide under the microscopy and/or change image magnification. The validity of telepathology diagnoses was assessed with kappa coefficients. Consultations were completed in 5 to 15 minutes per case. Sound transmission was unreliable, and in approximately 25% of consultations the referring pathologist needed to "call back" to reestablish verbal communication. In all but 2 transbronchial biopsies there was agreement between the original diagnosis and the diagnosis by telepathology (kappa = 0.92). In 48 of 58 endomyocardial biopsies there was concordance between the 2 diagnoses (kappa = 0.692). Only 3 out of 10 of these discrepancies were clinically significant (kappa = 0.897). Internet-based teleconferencing techniques provide effective and relatively inexpensive tools for real time telepathology consultations. The technology is probably best suited for the study of small specimens from patients that require rapid diagnosis by a consultant. 相似文献
142.
Mantovani A Bonecchi R Martinez FO Galliera E Perrier P Allavena P Locati M 《International archives of allergy and immunology》2003,132(2):109-115
After the identification of the interleukin (IL)-1 type II receptor as the prototype, decoy receptors have been identified for a number of members of the IL-1/IL-18, TNF, IL-10 and IL-13 receptor families. Moreover, the silent receptor D6 is a promiscuous decoy and scavenger receptor of inflammatory chemokines. The IL-1 decoy receptor is regulated by pro- and anti-inflammatory signals and its levels may serve as a readout of the activation of anti-inflammatory pathways, for instance by glucocorticoid hormones. Decoy receptors represent a strategy to tune inflammatory and polarized adaptive responses. 相似文献
143.
144.
Miranda-Vizuete A Sadek CM Jiménez A Krause WJ Sutovsky P Oko R 《Antioxidants & redox signaling》2004,6(1):25-40
Redox control of cell physiology is one of the most important regulatory mechanisms in all living organisms. The thioredoxin system, composed of thioredoxin and thioredoxin reductase, has emerged as a key player in cellular redox-mediated reactions. For many years, only one thioredoxin system had been described in higher organisms, ubiquitously expressed in the cytoplasm of eukaryotic cells. However, during the last decade, we and others have identified and characterized novel thioredoxin systems with unique properties, such as organelle-specific localization in mitochondria or endoplasmic reticulum, tissue-specific distribution mostly in the testis, and features novel for thioredoxins, such as microtubule-binding properties. In this review, we will focus on the mammalian testis-specific thioredoxin system that comprises three thioredoxins exclusively expressed in spermatids (named Sptrx-1, Sptrx-2, and Sptrx-3) and an additional thioredoxin highly expressed in testis, but also present in lung and other ciliated tissues (Txl-2). The implications of these findings in the context of male fertility and testicular cancer, as well as evolutionary aspects, will be discussed. 相似文献
145.
Postnatal development of dopamine receptor expression in rat peripheral blood lymphocytes. 总被引:1,自引:0,他引:1
Daniele Tomassoni Elena Bronzetti Franco Cantalamessa Fiorenzo Mignini Alberto Ricci Maurizio Sabbatini Seyed K Tayebati Damiano Zaccheo 《Mechanisms of ageing and development》2002,123(5):491-498
Postnatal development in the expression of dopamine D1-like and D2-like receptors was investigated in peripheral blood lymphocytes of male Wistar rats aged 1, 3, 4, 8, 12 and 16 weeks of age by radioligand binding assay techniques. Sample of frontal cortex, striatum and hippocampus were also investigated as reference tissues. The dopamine D1-like receptor antagonist [3H]SCH 23390 and the dopamine D2-like receptor agonist [3H]7-OH-DPAT were used as radioligands. The affinity (K(d)) of [3H]SCH 23390 or of [3H]7-OH-DPAT binding was unchanged in lymphocytes of rats of different age groups. The density (B(max)) of [3H]SCH 23390 binding sites increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 8th week of age, and then increased slightly at 12 and 16 weeks of age. The B(max) value of [3H]7-OH-DPAT binding to lymphocytes increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 4th week, increased again until the 12th week and then plateaued. Dopamine D1-like and D2-like receptor maturation in frontal cortex, hippocampus and striatum revealed an increased receptor density until the 4th week of age and a relative stabilization of receptor density values between the 4th to the 12th week depending on the area considered. Comparatively postnatal maturation of lymphocyte dopamine D1-like receptors displayed a pattern different from that of brain areas investigated, whereas maturation of D2-like receptors displayed a pattern similar to that of striatum. The quantitative and/or qualitative dissimilarities between development of lymphocyte and brain dopamine receptors suggest that from a developmental point of view lymphocyte dopamine receptors probably cannot be considered as a marker of homologous brain receptors. 相似文献
146.
Selected pool of peptides from ESAT-6 and CFP-10 proteins for detection of Mycobacterium tuberculosis infection 总被引:6,自引:0,他引:6 下载免费PDF全文
Scarpellini P Tasca S Galli L Beretta A Lazzarin A Fortis C 《Journal of clinical microbiology》2004,42(8):3469-3474
We have validated a new test for detecting Mycobacterium tuberculosis infection. A pool of synthetic peptides derived from ESAT-6 and CFP-10 proteins was used to detect the number of specific gamma interferon-producing T cells by means of an enzyme-linked immunospot assay. Sixty-eight individuals positive for M. tuberculosis infection, either human immunodeficiency virus-seropositive or -seronegative, were studied. The test results were highly specific (87.5%) and sensitive (93.1%), more so than a classical lymphoproliferative assay (specificity and sensitivity of 77.27%), opening new possibilities for diagnosis and screening of tuberculosis. Moreover, the test allowed us to distinguish individuals infected with M. tuberculosis from those vaccinated with BCG. 相似文献
147.
A novel missense mutation in exon 3 of the COL4A5 gene associated with late-onset Alport syndrome 总被引:1,自引:0,他引:1
Alberto E. Turco Sandro Rossetti M. Olivia Biasi Gianfranco Rizzoni Laura Massella Niina H. Saarinen Allessandra Renieri Pier Franco Pignatti Mario De Marchi 《Clinical genetics》1995,48(5):261-263
We have identified a novel missense transition (362G→A) in exon 3 of the COL4A5 gene in a male patient with late-onset Alport syndrome. We used non-isotopic single strand conformation polymorphism, heteroduplex analysis, and automated DNA sequencing. The mutation changes a conserved glycine at codon 54 for an aspartic acid (Gly54Asp), which abolishes a BstNI site. Using restriction analysis, we identified the heterozygous carrier status in the two daughters of the proband. Our findings are in keeping with the hypothesis that slower progressive forms of Alport syndrome are more often associated with missense mutations rather than large deletions or frameshifts. This is the first mutation described in the N-terminus triple helical 7S domain of the COL4A5 gene in an Alport syndrome patient. 相似文献
148.
Molina Inmaculada; Santana Antonio G.; Pla Marcial; Romeu Alberto 《Human reproduction (Oxford, England)》1994,9(3):413-416
In 18-week-old nulliparous rabbit dose, ovulation was inducedwith 50 IU of pure urinary luteinizing hormone (LH; LHgroup),or 50 IU of ohuman chorionic gonadotrophin (HCG; HCG group),in order to detemine the effect of these treatments on 17-oestradioland progesterone concentrations, and on oocyte and embryo quality.Luteinizing follicles, recovered oocytes, progesteronoe concentrationand grade 5 embryos were significantly reduced when pure urinaryLH was used. Statistically significant correlations were found:(i) between oestradiol concentration and number of degeneratedoocytes in both groups (positive); (ii) between oestradiol concentrationand grade 1 and 2 embrayos (negative), and grade 5 embryos (positive)in the HCG group; (iii) between progesteronoe concentrationand metaphase II oocytes(negatice), and between progesteroneand grade 5 sembryos (positive), in the HCG group; and (iv)between progesterone and oestradiol concentrations (negative)in the LH group. It seems that the oestrsdiol to progegsteroneratio improves during the early luteal phase when ovulationis induced with LH, and that oestradiol and progesterone concentrationscould play a role in dtermining oocyte and embryo quality 相似文献
149.
Mixed epithelial and stromal tumors of the kidney. A report of 22 cases 总被引:16,自引:0,他引:16
Michal M Hes O Bisceglia M Simpson RH Spagnolo DV Parma A Boudova L Hora M Zachoval R Suster S 《Virchows Archiv : an international journal of pathology》2004,445(4):359-367
Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison. 相似文献
150.
Michael Frenken Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1985,328(3):301-303
Summary Large coronary arteries of the dog were contracted with 5-hydroxytryptamine (5-HT). The 5-HT2-receptor antagonist ketanserin antagonized the 5-HT-induced effects. Unlike Brazenor and Angus (Europ J Pharmacol 81: 569–576, 1982), who reported insurmountable antagonism of the effects of 5-HT in dog coronaries, we found that the antagonism by ketanserin can be surmounted, provided the concentrations of 5-HT are high enough. Ketanserin also unmasked a saturable component of the 5-HT-induced contractions. Although ketanserin (0.1–1 mol/l) depressed the maximal force of the saturable component, it did not change its EC50 (-log mol/l 8.0). We conclude that large coronary arteries of dog are contracted by 5-HT mainly though 5-HT2-receptors and to a smaller extent through receptors different from 5-HT2. 相似文献